Telephone-exchange system.



A. E. LUNDELL.

Patented Sept. 3, 1918.

9 SHEETS-SHEET 2 In for A/ken L un d? A. E. LUNDELL. TELEPHONE EXCHANGE SYSHM. APPLICATION FILED IUNE 11. ms.

Patented Sept. 3, 1918;

9 SHEETS-SHEET 3 an W i n t \R 2 3 L wk 5 Hann Im/enfor A/ben E. Lundel l.

'Aff'y.

A. E.- LUNDELLQ TELEPHONE EXCHANGE SYSTEM.

APPLlCATlON FILED JUNE 11. 1am.

Pan-11ml Sept. 3, 1918.

r A. E. LUNDELL.

IELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED JUNE IT. l9lt5.

Patented Sept. 5, 1918.

9 SHEETS-$HEET I lm/en for; A/ben E. Luna/ell.- y

v A. E. LUNDELL. TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED IUNE 11. I916.

Patented Sept. 3, 1918.

I lnvewfok: A/ben Lunae/L A y,

UNITED- STATES PATENT OFFICE.

ALBEN E. LUNDELL, OF NEW YORK, N. Y., ASSIGNOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N, Y., A CORPORATION OF NEW YORK.

TELEPHONE-EXCHANGE SYSTEM.

Specification of Letters Patent.

Patented Sept. a, 1918.

Application filed June 17, 1916. Serial No. 1Q4,231.

To all whobi z't ihay concern:

Be it known that I, ALnhN E. LnxnizLL, a citizen of the United States, residing at New York, in the county of Bronx and State of New York have invented certain new and useful Improvements in 'lclephrmel lxcliange Systemsot which the following is a full, clear, concise. and exact dcscription.

This invention relates to telephone exchange systems and more particularly to a telephone exchange system in which a connection may be established between a calling lineand :1 called line, either by means of automatic selector switches or by means of manually operated apparatus.

The object of the invention is the pro vision of a sending device which may be op erated to impress upon a connecting circuit over which the call is established, either controlling impulses for controllingthe operation of automatic switches, or audible signals for announcing to an operator the designation of thecalled line, depending upon whether the particular call is to be established by means 01': automatic switches or by means of manual apparatus.

A feature of the invention, therefore, re-

lanes to the provision-of means for causing the sending device to operate in either one oftwo ways, which means in the particular systems disclosed includes keys adapted to be set by an operator inaccordance with the desi ation of the desired line. If the desir line can only be reached by means of {automatic switches, the operator will depress a'key which will automatically eliminate the connection of theaudible announc- .ing neanstothe connecting circuit, whereas if connection totlie desired line is to be es tablishil by means of another manual operator, the first operator will depress a key which-will automatically connect the audible'announcing means to a sedond operators telephone to enable such second operator to extend the connection to the cl'sired line.

In accordance with another feature of the invention, provision is "made whereby the audible -announciligmeans, havingbeen conneoted to the telephone of the second 'oper tor, may be disconnected therefrom .either automatically or by manual means under the control of either operator.

Still another 'tcature of. the invention relatcs to the use of an automatic switch which. controls the association of a sending device, first to control the extension of a. call ng i'iue to a trunk line leading either to an automatic selector switch or to an opei'atofis gmsitiom and to connect such sending device to such connected trunk. This aummatic switch. sub sequently performs either one of two other operations, one being the association of means for audibly announcing the number of the desired line with the connected tiiunk, and the second being the association of means for impressing controlling impulses with the connected trunk.

In the accompanying drawings, Figures 1.. to 10 inclusive show a telephone system adapted for both manual and semi auto matic working and to which the invention is applied, enough of the telephone system be ing shown to explain the use of the inven tion in connection therewith. layout of the various figures showing how the same should be placed when reading the description thereon. v

The invention will be most readily understood from a description of the operation of setting up a call and establishing the desired connection.

There are several cases which may arise. The call to be extended may be one to a regular oflice in a manual exchange, or one to a subscriber on a party line, or'the call may be extended-to a subscriber in a semi-autm Itwill be assumed that the number of the wanted subscriber in all cases is 123, except that in the case of a call toll subscriber on a party line, the subscribers number will be M- 123.

If the call is to a subscriber on a party line in a manual. ofiice, subscriber 100 rcmoves his receiver from the switchhook, closing a,circuit in the usual manner-through the'line relay 105 and lighting the lamp 106 Fig. 11 a at thecentral ofiice. The Aoperator whose net an leadin to the subscriber 100. The insertion 0 this plug into the jack closes a circuit; from battery, through cut-ofl' relay 110, ja ck 109, plug 108, rela 111 to ground, energizing both the cut-0 relay 110 and relay 111. The energization of cut-off relay 11'0 cuts off the line relay 105,and extinguishes the lamp 106. The energization of relay 11.1 completes a circuit from battery, motor magnet of district sequence switch 101, lower left contact of sequence switch spring 112, arn'iature and front colitactof relay 111, energiz ing the motor magnet and moving. sequence switch 01 out of position 1 and into position 2. In position 2 of sequence switch 101, a circuit is'completed from battery, motor magnet of sequence switch 300, upper left,

contact of sequence switch spring 305, conductor 306, sequence switch spring 1.13 to ground, energizing the motor magnet-and moving sequence switch 300 out of position 1 and into position In position 2 of sequence switch 300, a circuit is closed from battery, through the up magnet 30? of the cord finder, sequence switch contact 303, left armature and back contact of stop relay 309 to ground, energizing the up magcausing a movement of the brush carriage to move the brushes 310, 311, 313, 31-1 over the contact bank in search of the terminals-315g 316, 317, 318 of the trunk taken for use. \Vhcn the terminals are reached, a circuit is closed from battery, stop V switch spring 305, left armature and front contact of stop relay 3,09, moving sequence switch 300 from POSltlOn 2 into position 3. In moving out of position 2, sequence switch 300 breaks, at the upper contact of sequence switch spring 319, the energizing circuit of the stop relay 309, but this relay is held energized over a circuit from battery, windingof stop relay 309, lower contact of se quence switch spring 319, right armature and front contact of the stop relay, conductor 329, brush 313, terminal 317 to ground at the upper contact of sequence switch spring 104, which ri ircuit will be maintained until after sequehce switch 101 m---ves out of position 11. 4

' While the above operation has been taking sa ke of clea rness.

place, the A o 'ieralor has (lopmsscd her listening key 114, placing her telephone set 107 across the line, and has rccciwd from the calling subscriber 100 the designalion of the wanted line, which I hare assumed to be M--l23. llaring received [his designation, the. A opcralor depresses the oli'ice hey 401, corrcs mnding to the ollii-e in which lhe. wanted subscriber is located. aml the-n depresses the No. 0 her in the [000s row, thev No. 1 in the l00s, the No. 2 key in the 10 the No. 3 key in the unils, and the M key in the stations bank of keys. as indicated on Fig. 0, it being assumed llnu. each of the. keys diq'iresscd represents one out of a bank of ten keys, the remaining licys 01' the bank being omitted from the drawings lor the The depression of lhe ofiice key 4.01 puts a ground. on the conductors 40; and 4023 leading lo the class and brush register sequence switch contact springs, res 'iectively. while the elosiric of the 0, 1. 2, 3, and 1" keys places a ground on the 1000s. 1003;, 'l0s, units and stations register sequence. switches respectively. \Vhen sequence switch 300 reaches position 2 the following circuits are now closed: from battery. motor magnet of class register sequence switch 4-00, right armature and contact of cut-oil relay 104, comluclor 405, sequence switch contact spring 320 to ground; rom battery, motor magnet of brush register sequence switch 410, right armature and ci'mtaet. of cut-oti' relay 4-00, conductor 405 and to ground. as above traced; and from sequence switch springs 321, or 32". conductors 323, 2521, 325, 326 or 327 through the motor magnets of the 10001 100s. 101s. units and stations register sequence switches. respectiretr. right armature and contact of the cutoff relays 00 to 004. inclusive, of the 1000s. ltltls, 10s. units and stations bank of keys, to the conductor Ali") and to ground at sequence switch spring 320. The class register sequence switch 400 will continue to rotate through its various positions until position 111 is reached, at which time a circuit is closed for the cut-elf relay 404 at the upper contact of sequence switch spring 407, energizing the relay 401 and stopping the sequence switch in this position. Brush register sequence switch 410 rotates until a circuit is closed for the-cutofi relay 400 at the upper contact of sequence switch spring 408; stopping the sequence' switch 410 in position 2. The 1000s sei piencc switch will continue to rotate until a ground is encountered on the lower contact spring of said switch when the following circuit is established over the 'cut-ofl' relay 600; from battery, relay 600, lower contact in the 1000s' sequence switch, the No. O1 000s key to ground. The No. 1 key energizes the cut-off relay 601 to stop the 100s sequence switch in position 1. The No. 210ske energizes the cut-off relay 602 to stop t e 10s sequence switch in position 2. The No. 3 units 'key energizes the cut-01f relay ,603 to stop the units sequence switch in position 3. The stations key M energizes the cut-ofi relay 604 to stop the stations re'gister seuence switch in. position 3, which is a position corresponding to station M of a party linel The energization of the cut-off relays completes a circuit from battery, motor magnet of sequence switch 300, lower right contact of sequence gwitch spring 305, con- --(-luc tor 328 througi'i the right armatures and contacts of the cut-off relays in series to ground, to move sequence switch 300 from' position 3 into position 8.

In passing into positions and until passing out of position 7, sequence switch 300 at the upper contact of sequence switch spring330 maintains a circuit for the release magnets 409 and 411 of the class and brush register keys and also the release magnets of the numerical and stations bank of keys (not shown), releasing. the depressed keys in the usual manner.

In passing to position 1, sequence switch 300 completes a circuit from battery, motor magnet of sender sequence switch 500, contact of sequence, switch spring 511, 'conductor 512, lower contact of sequence switch spring 302 to ground, moving sequenceswitch 500 from position 1" int o osition 4. In coming into position 2, a circuit'is closed 1 from bpittcry' of motor magnet of Sender sequencelswitch 500,-conductor 513, outer right armature and contact of relay 510,: contact -of sequence switch spring 514, conductor 515, lowercontact of sequence switch spring 3041 toground, mo ing sequence switch 500 from position 1, through position 7 into position 8-. r

\V'th' district switch 101 in position 2,

"cord finder sequence switch 300 and sender sequence switch 500 in position. 8, a fundamental circuit is established from battery, 'relay 115, upper contact of sequence switch spring 116, conductor 117, terminals 316., brush 311, conductor 331, upper armature and back contact of relay 303, contact of sequence switch spring 332, conductor 333, left armature and back contact of the 0 counting relay, through the stepping relay 516, seql'i'ence switch spring 517, inner right armature and back contact of relay 510, conductor 518 to ground at sequence switch spring 302 s vepping relay 516 energize in this circuit, the relay 115 at its right armature and front contact completing a cirduit at the upper contact of sequence switch spring 118 to move sequence switch 101 outof position 2 and into position 3,"and at itsleft armature and front. contact completing a shunt circuit-1 Both the relay 115 and the I through lower right and left contact of sequence switch spring 116, conductor 1 19, commutnto fS gment 120-to ground at the brush 121. which is for the purpose of shunting the stepping relay. Sequence switch 101, in comin r into its third position, completes a circuit rom battery, through the up mag net 122, contact of'sequence switch spring 124 to ground-at the right armature and front contact of relay 115, energizing the inagnet v to...cause upward..,movcment of the he brush carriage 1 25 moving. upwardly completes the shunt circuit from ground at the brush 121. Each time such brush passes 'over one of the commutator-segments 120, it shunts the stepping relay 516 which, de-

- energizing, breaks the circuits above traced for the No, 2 counting relay, allowing the No.'2' counting relay to energize, extending the energizing circuit,

which formerly passed through the No. 2 relay, to now pass through the No. 1 counting relay. The brush carriage 125 will'move upwardly until the stepping relay has been energized and deenergized' three times, at which time the 0 counting relay will have energized, attract ing its'armatures, reaking the fundamental clrcuit above traced 'at'its left. armature and contact, causing the denergization of the relay and the stepping relay 516. Relay 11 5, deenergizing, broke, at its rightarm'a ture and front contact, the circuit fort'he up magnet 122, stopping the upward movement of the brush carriage 'withthe brushes 126, 127 and 128 in engagement with the terminals 129, 130and 131, respectively,

of a trunk leading to a 'B o'perators position,-and at its right armature and back contact, completing a circuit to move sequence. switch 101 out of position 3 and'into osition '11. Although, for the sake" of erators position, it, will be understood by 120 revity, the motion of this switch, under the 5 control of the counf in'g re1ays,has been de scribed as placing the terminals of the switch on a'trunk line leading toa B opof relay 203 completes a 'inafter described.

ment. which ort'linarily takes place in positions r to 10 of sequence switch 101, is for the purpose of selecting an idle trunk in said group. The cncrgizalion ot' the 0 counting relay at. its right armature and front con act completes a circuit from hatter). motor magnet o'l sender sequence switch 500. right -rniature and trout contact of the. counting relay. conductor 522. left armature and back contact of relay 510 to ground at sequence switch spring 523, moving sequence switch .300 out of position 8 and into position 5 in position 9, a circuitis closed for sender sequence switch 500 at the upper contact. of sequence switch spring 511 and lower contact of seql'iencc switch spring 304 to more the sequence switch 500 out of postion 0. through posilion 1? and back into position 1. A circuit is at this time closed from battery, contact of sequence switch spring 330. comluctor 35-17. through the relays 507 and 500 in series, comluctor 524 to ground at sequence switch spring 410. lhe energization of relay 507 closed a circuit which may betraced from battery.rclay ittil. conductor 3 in.upperarniature and contact of slow acting relay 502, con ductor 525. left armature and back contact of relay 503. energizing winding of relay 510. upper armature and front contact of relay 5107. contact of sequence switch spring .320 to ground at lower contact of sequence switch spring 330. energizing in this circuit the relays :503 and 510. circuit. is now completed from battery. line relay 201, conductor 223. upper left winding of repeating coil 224. terminal 129. brush 120. lower contact of sequence switch spring 132, conductor 11?. terminal 316. brush 2311. conductor 331. upper armature and from contact of relay 303. upper right winding of repeating coil 301 togronnd. energizing the line relay 201 which attracts its armature, completing a circuit from battery. through thehigh and low resistance windings of the local relay 202 in series. armature and contact of line relay 201 to ground. energizing the local relay 202 which completes a circuit from battery, right armature, contact 225, contact 2-20, conductor 227. relay 203, relay 204: to ground, e1: 'n'gizing both said relays which attract their arnnlt-ures. The energization circuit from battery. lock-in relay .205. lower arnlature. and front contact of relay 203. conductor 228 to ground at thearmature of relay 206. When relay 205 energizes, av circuit is completed from battery, through the trunk lamp 212 to ground at the interrupter;i313, which causes the trunk'lainp 212 to flash until the B operator answer the, call, as will be here- Also, relayf205, when energized, completes at its upper armature a locking circuit for itself which will be u maintained as long as relay203 is energized.

This locking circuit. ma be traced as follows: from battery, tirongh relay 206, through the relay 207 and telephone relay 208 in parallel, the upper winding of relay 205, upper armature thereof to ground at the upper armature of relay 203. llclays 200,207 and 208 are now energized, the relay 200 at its right armature and track contact removing ground from the relay 205 and also ground from any other corresponding relay 205, preventing any other trunk from coming in and connecting to the operator until the present call is attended to. Relay 208 being energized attracts its arlnatures and connects the B operators telephone set, 801 across the line and in position tohear the wanted subscriber 1 )lionographically.

As soon as relay 208 is energized, a circnit is closed for relay 211. from battery, lower right winding of repeating coil 221, lower armature and front contact of relay 20s through retarding coil 818. repeat key 817, upper armature and lower contact of relay 20S. upper right winding of repeating coil 224 to ground. The energization of relay 211 closes a circuit for relay 312 which may be traced as follows: from battery, lower right winding of repeating coil 301, ,relay 312, lower armature and contact of 302-}, brush 310, terminal 315. lower contact of sequence switch spring 137, brush 127, terminal 130, lower left winding of repeating coil 22%. conductor 9, left arn'iature and contact of relay 202. lower arn'iature and contact of 207, retardation coil 10. contactand armature of relay 211 to ground. The.

energization of relay 312 closes a circuit from battery. through a slow acting relay 501, conductor 527. arn'iature and front eontact. of relay 512 to ground The relay 501, at its armature and front contact, coinpletes a circuit to energize the slow-acting relay 502, which attracts its arn'iatures, at its upper armature cutting off the shuntaround the relay 503, whereupmi said relay 503 is energized in series with the relay 303' and 510. Relay 502, at its'lower armature and front. contact, closes a circuit which may be traced from battery. left armature and front contact of relay 503, lower armature and frontcontact of relay 502, conductor 328, right armature and back contact. of relay 509, relay 50-1, conductor 529 through the. interrupter contact- 700 on the phonograph sending device shown in F ig. 7. The circuit, however, above traced, is intermittently made and broken. being made when the outer end of one of thecams of the contact 700 rides up on the cam surface 701 of the cam 'ti'02, which cam is mounted on a shaft 703, which is driven by the usual gearing from the main shaft 704 from the phonograph device. VVl:en relay 501 is energized, a circuit is completed from battery: through the motor magnet of the v I A sender sequence switch 500, cohduetor-513, armature and front contact of interrupter relay 504C to ground at sequence switch spring .530, moving the sender sequence switch from position 1 into position 4. As

. the shaft 704 of the phonograph device rotates, the end of the contact spring 700 moves off the cam face 701, breaking the energizing circuit for the interrupter relay 504;, which thereupon dcenergizes, closing at its armature and back contact", and left armature and front contact of relay 510,. a

circuit to move sender sequence switch 500 from position 4: into positlon 5. In Fig. 7 is shown in schematic form a phonograph call indicator. A plurality of disks, of which but one (705) is shown, a re '4. 5, 0 and 7 recorded thereon, while the fourth recorded thereon the numerals and. 9. .Rcprodu'cing magnets 706, 707,

708 and 709, shown in perspective, and the other magnets to'reproducethe letters and remaining numerals, are similarly mounted.

The disk 705 being constantly rotated, when a circuit is closed through the reproducing magnet 700, 707, 708, or 709, the numeral or letter or other character desired is re produced inthe circuit including the repro- (lacing u'lagnets 700, 707, 708 or 705) and repeated in the telephone of the B operator, who tlius-hcars the numeral or other information.

The record on the disks, as shown by the dotted lines 0, 1 2, 3 on disk 705, does. not extend in a complete circle thereon. The are of the circle on which no record appears is so spaced with relation to the cam surface 701 as to permit the interruption of the circuitfof relay 504 at the proper time to allow. sender sequence switch 500 to move from one position to the next, .so thatthe switching operation takes place between words. f

In position5 of sender sequence switch 500; a' circuit is closed from the common return conductor 710, the M reproducing magnet lll, through the amphficrset 712,

. I co? luctor 41.3. upper contact of sequence switch spring 605, conductor 006, lower left contact. oi sequence switch spring 505, condin-tor 531, armature and contact of relay 500. the conductor 532, through the lower and upper left windings of repeating coil.

"301, back through the common return conductor 710. The circuit for reproducing magnet 711 being completed, and the disk with which said magnet is associated being constantly rotating, the word M in this instance will be reproduced in said circuit and repeated by the repeating coil 301 into the repeating coil 22%, \vhere it will be repeated into the B operators set 801. At this instant. 'contact 700 is again closed, energizing the interrupter relay in the .manner before described, and closing, at its'armature and front contact, a circuit to move sequence switch '500 out of position 5 and into position 6. In position 6 of, sequence switch 500, a circuit is closed from the common re- ,turn conductor 710, through the left side :of

repeating coil 301, through conductor 532,

armature and contact of relay -F06, conductor- 531," upper contact of sequence switch sprin 533, conductor 534, lower contacts of 1000 s described for station M, re eating the numeral 0 to the B operator. has been transmitted, the circuit for the in:

en this word terrupter relay 504 isagain broken at the contact 700, closing a circuit for sender sesequence switch spring 607, conductor608,

quence switch 500, movingit out of position 6 and into position- 7, in which position a circuit is closed in the now well'known man ner through the No. 1 reproducing nagnet 707, the circuit inthis instance (being completed at the upper right contact of-the s sequence switch contact spring 609.

In like manner, the circuits for.- the reproducing magnets 708 and 709 are completed to reproduce the numerals) and 3 to the B- operator. It will be noted that the circuits for reproducing magnets 708 and 709-are closed in sequence switch positions 9 and 10, respectively, of sender sequence switch 500,

and that no reproduction takes place in position 8 of such sequence switch. .Thisis according to the usual telephone, practice where a numberconsisting of four-digits always has a pause between the second and third digit. When the last di 't 0; the number has been transmitted,. he circu t through the interrupter relay. 504 is broken,

allowing its armature tojretract-and closing. a circuit for sender sequence switch 500 to 120. .moveit out of position 10 and into position 11. In position 11, when contact 7 00 is again made, interrupter relay 504 isener gi'aed, attracting its armature and completing the circuit to drivesequence switch 500 contact 700 "is again opened,-interrupter re from position 11 into position 12. When lay 504 becomes energized, at armature l v and back contact completing a circuit to drive sequence switch 500' from position 12 into position 13. i This alternate making and breaking oi the circuit. of interrupter relay 504 advances the sender sequence switch 500 through ts various positions back into position I. 'hen the. sender sequence switch is in position 10, if the key 540 is closed, a circuit is established from ground, through said key 54-0. through the relay and sequence switch contact spring .308 to battery at either of the slow acting relays 501 or 502, ei'iergizing the relay 500. which attracts its armatures. breaking the circuitfor the interrupter relay 504. It the key 546 is not closed, the. number will be repeated indefinitely. During the transmission of the called number to the li operator, the trunk lamp 212 has been flashing due, to the operation of the interrupter 21 The B operator now takes the plug 000 on the end of the trunk taken for use and tests the wanted line. in the usual manner. it the wanted line is not busy, she plugs into the multiple jack 9 1. leading to such subscriber. .llugging into the jack 901 completes a circuitfrom battery. through the second plug relay 215,1irst plu; relay 214, sleeve of plug 900, sleeve contact of jack 901, cutoti relay 902 to ground, energizing the three relays described. The cut-off relay 002, at its arniatiires, pi'cvciitsline relay 003 from energizing, thus preventing the lighting of line lamp 904. The energization of relays 2H and 215 completes a circuit from battery, through the resistance 210. lower armature and front contact. of relay 214-. right contact spring of relay 21b. right armature and front contact of relay 204, through the high resistance. winding of relay 21 to ground at the upper contact ot ditlereutial relay 217. Relay 218 energizes and, at its left armature, opens the energizing circuit. of the relay 203, and relay 203 opens-the 'ei' ergizing circuit for relays-205, 206,207 and 208, The deenergization of relay 208 removes the opers ators set 801 from the trunk and (leinch gizes the sup'er'vist'iry relay 211. Supervisory relay 21.1, dee iergizing, breaks, at. its

o dare and-contact. the-energizing circuitv tor the. relay 312. Relay 312, deenergizing,

' finder.

breaks the energizing circuit for the slow acting'relays 501-, 502 and-509. The relays 503 and 510, however, remain energized after the deenergization of relay 502 over a circuit which may be traced from battery, right: armature and front contact of relay 503, co'nductor525, upper armature and back contact, of slow acting relayb02, through the energizing winding of relays,5 03 and 510 in series, right armature and fiont contact. of said relay 510, conductor 518 to ground at the sequence switch spring 302 ofothe cord Relay 303 is, however, shunted out, and, on detinergizin disconnects the repeating coil-301 from the trunk. Slow actingrelay 502 deenergizing, a circuit is completed at its lower armature and back contact from battery, left armature and front contact of relay 503, lower armature and back contact of relay 502, through relay535 to ground, energizing said relay 535 and completing a. circuit from battery, through motor magnet of cord finder sequence switch 300, conductor 310, sequence switch spring 341, position 8, condiictor 342, armature and front contact of relay 535 to ground, moving cord tinder sequence switch from position 8 and into position 15. \Vhen relay 303. deenergized, cutting off the repeating coil 301 from the t-runk, it broke the energizing circuit of relay 201, which, at its armature and front contact. broke the energizing circuit for the local relay 202. This relay 202, in

"turn deenergizing', breaks, at its right; armature and contact, the circuit for relay 201. The deencrgization of relay 2.04 removes, at its right armature and front Contact, the shuntarouud the relay 219, which thereupon. energizes. This circuit is from battery, resistance 210, armature and spring of relay 214, lower spring of relay 207, upper wind-.

.ing of relay 207, winding of relay 219, right armature and back contact of relay 204, and

lower winding of relay 207 to ground.

On cord finder sequence switch 300 coming nto position 15, a-circuit is closed from .95 district sequence switch 101, lower right spring 132, upper right winding of repeat-' ing coil 102 to ground, energizing theline relay 201, which, intiirn, energizes local relay 202.

As the relay 218 is still energized "and relay 204 denergized,acircuitis completed from battery, through winding of relay 220;

left armature and back" cont act of relay 204, left armature and contact of relay 218,

right armature and Swingin'gc'ontact of local relay 202 to positive battery. The energization of this relay 220 in turn completes a cira ciiit from battery, right-armature and front' 1 20 I winding of relay 218', lower winding of'dif l ferential relay 217. energizing the rel-ay21ll',

contact of said relay 220, low resistance which, at, its lower armature and contact, breaks the energizing circuit, for relay 219. The deenergization of relay 2-19 completes a circuit. from battery. through the relay 22.1, upper winding of relay 207, up er armature and back contact of relay 219, low resistance winding of local relay 202 to ground at the armature and contact of line @231, inner armature andfifront contact of relay 201. Relay 221 attracts its armatures, connecting the source of ringing current 229 or 230 to the cordleading to the called subscriber. i 5 I It will be remembered that the cord finder sequence switch 300 has come into position 15, and that a circuit-for relay 309 has been maintained at either the upper or lower contact of sequence switch spring 104 in positions 2 to ll of the district scquence switch 101 anclin positions 2 to 16 of cord finder sequence switch 300. \Vhen district sequence switch 101 passed out, of' osition 11, energizing circuit for the relay 309 is broken at the upper contact of se- 'quence switch spring allowing relay 309 to decnergize, completing a circuit from battery, through 'motor magnet of: sequence switch 300, conductor 340, contact of sequence switch spring 308, left armature and back contact of relay 309 to ground, moving sequence switch 300 from position to position 17, in "which position, the sender sequence" switch 500 being in position 1, a circuit is closed from battery, through the down magnet 342, conductor 343, upper contact of sequence switch .spring 537 to ground at sequence switch spring 339, moving the brush carriage carrying the brushes 310, 311, 313 and 314 downward to their initial position. \Vhen the brush carriage reaches its lowermost position, the o'ff-norinal contact 344 is closed, completing 9. oil! cuit from battery, through mot-or magnet. of cord finder sequence switch 300, upper right contact of'sequence switch spring 305 to ground at the off-normal contact 344, moving the cord finder sequence switch 300 from position 17 into position 1.

. The cell being to a subscriber on a. party line, the B operator,-before inserting the ,rplug 900 into the multiple jack 901, depresses theproper ringing key 231 so that. when the line. hasbeen tested, and found to idle and the plug inserted, the proper current front-sources 229 or 230 may be projected over the outgoing line'to ring the calling device at the subscribers station. A reley 222 is in series with'the source of curretirees) or 230, and is of suchdhareter, 1that it-flwill not respond to the intmmittent 'curienttfrom such source when this current is passing through the same in series with thecalling device and condenser at thesub- Q {staitiombut when the subscriber removes his receiver gfrom the .switc'hhook, cutting out the calling device and condenser, a circuit is closed which may be. traced from the source. of current 229 or 230, the energizing winding of relay 222, the depressed key ,reley- 221, contact of substation set. back through tip contact; oi jack 901, the tip of plug 900, upper mm the ring of the plug 900,1'ing subscriber being on a straight line as-dis- P tt-11$- sh w in lack- 901, through the sub I ture and swinging contact of first plug relay 214 to ground at the outer armature and front contact din-clay 221. Relay 222 ener- 'zes in the circuit just traced, attracting its armature and breaking the. energizing circuit for the relay 221, cutting off the ringing current and completing the con nection through from the calling to the called subscriber. The call is supervised in the usual manner, but as this operation forms no part of the present invention, it will not be described.

In the case ofa manual operationirom one calling subscriber to another, the-other tinguishedfrom aparty line, the operation above described is repeated, except that the key for setting the stations register sequence switch shown in Fig.0, is not depressed, and therefore the phonogre h record of the station is not operated. The call, however, progresses in the same way, and the same ringing apparatus is brought into use.

In the case, however, of a call to asemiautomatic oilice where the switching operation is under the control, ofv the central operator, the B operator is eliminated entirply, the call being under thesole control of the A operator. If we assume that the call in this instance is to a subscriber,

nu nbered 0123 located in a semi-automatic o 'e, the A operator receiving the required information from the calling subscriber'd'e. prtsses an appropriate oilice key 417 to set the class and brush register sequence switches 4:00 and 410, respectively, in posiselect a trunk leading to the semiautomatic office. She then, as before, de-

presses the No. 0 1000s, No. 1 s, No. 2

10s and No. 3 units keys toset their respective sequence switches in the pro or position for transmitting these digits. 1 he operation of the cord finder shown on Fig.

3 is identical with that above described.

Therefore as the sequence switch 300 reaches position 2, the class and brush register sequence switches and the-thous kids, hundreds, tens and units s uence slygitches' are started in motion; as be ore. e depres 11p sion of ollice key 417 completes aicirc'uit for:

the cut-off relay 40-! when the class register sequence switch 400 reaches position 5 and.

completes a circuit for the cut-oif relay'iOfi i s when the Referringto Fig. '5, it will be noted-that relays 506 and 50 7 are the relays. Whichdetermine whether" or not the phonograph up- Fig. 5 all in "ding 'a call; It will be noted that? I cuit for, these twb releysr'fi'sYonly clgj ed when the class register sequence 'switcliim.

is in position 16. Therefore, in the present instance, these relays 506 and 507 will not be energized, but the setting of the 1000s, 100s, 10s and units register sequence switches will be used tocontrol switching apparatus to extend the call under the sole direction of the A operator. As before, the cord finder will be connected with the district apparatus shown in Fig. 1, and district sequence switch 101 will lnove through positions 1, 2, 3 until it stops in position 11, where, as before, in response to the setting of brush register sequence switch 410, the brushes 126, 127 and 128 on brush carriage 125 will be moved over the proper bank of contacts and brought ,to rest in engagement with the terminals 13A, 135 and 136 respectively, of a trunk leading to the semiautomatic oflice shown in Fig 8.

The present invention is not concerned with the detailed circuits and apparatus located in the sen'ii-automatic oflice. This apparatus may be of the type disclosed in patent to A. E. Lundell No. 1,168,319 of January 18, 1916. Therefore, in Fig. 8 the connector switch .is merely indicated by the brushes 809 and 810 and the terminals 814 and 815. The usual connector sequence switch 800 is also shown as well as the line relay 802. The usual interrupter or commutator carried by the connector switch is not shown, but a conductor leading to such commutator is indicated 2113813.

\Vith the sequence switch 800 in position 1, district sequence switch 101 in posi -tion 11, cord finder sequence switch in position 15, and sender sequence switch 500 in position 8, a fundamental circuit is established from battery through line relay 802, sequence switch spring 803, lower contact, conductor 801, terminal 134:, brush 126, lower contact of sequence switch spring 132, conductor 117, terminal 316, brush 311, conductor 331, inner armature and back contact of relay 303, sequence switch spring 332, conductor 333, left armature and back contact of counting relay 0 through stepping relay ,516, sequence switch spring 517, inner armature and. back contact of relay 510, conductor 518 to ground at sequence switch spring 302. I The line relay 802 and stepping relay 516 energize in this circuit, relay 802 completing a circuit which may be traced from battery through the motor magnet of sequence switch 800, lower contact of, sequence spring 805, armature and frontcontact of line relay 802, to ,ground, moving such sequence switch froirifqiosition 1 into position In position 2 the sequence.

switch 800, the usual energizing circuit is established for the power magnet of the con? neetor, starting such connector in its pre' liminary or brush choosing operation. As the connector moves, the commutator carried thereby intermittently places ground on the conductor 816, and, through the sequence switch spring 611 in position 2. places a shunt. around the stepping relay 51.6, causing such stepping relay to he intermittently energized and ilei uergizrtl until the fululaineutul circuit is opened in the usual manner in res iouse to the operation of the (bunting relays. 'hen he last;

counting relay is energized, a circuit; is

contact of relay .802 to ground.

The deenergization of relay 802 also opens the circuit of the power magnet: of the con nector and stops the movement thereof.

In position 3 of the sequence switch 800 and position 10 of sequence switch 500, the fundamental circuit is reestablished and the relay 802 again energized. In response to this energization of relay 802, a circuit is V established from ground, armature and front contact of relay 802, sequence switch spring 805 top, motor magnet of sequence switch 800, to theungrounded side of battery, moving the sequence switch into position 4.

In position 4"of the sequence switch, the connector is started in motion and the commutator carried thereby intermittently places ground on the conductor 813, and, through sequence switch spring 811 in position 4, intermittently to the stepping relay 516, causing such stepping relay to be intermittently energized and denergized until the fundamental circuit is opened in the usual manner in response to the operation of the counting relays, thereby terminating this-selection. The energization of the last counting relay closes'a circuit to-drive sequence switch 500 into position 12.- Upon the opening of the'fundamental circuit, relay 802 deenergizes and at its back'contact closes a circuit from battery, motor magnet of sequence switch 800, sequence switch spring 816 top, back contact and armature of relay 802 to ground. Sequence switch 800 moves to position 5, and awaits the reestablishmcnt of the fundamental circuit. When the fun IIO damental circuit is reestablished, the re tcntly placesground on: the conductor 813,

and, through sequence switch spring 811, in position 6, intermittent] to theste ping relay, causing such stepping relay to e intermittently energized and dencrgized until the fundamental circuit is opened in the usual manner in response to the operation of. the counting relays, thereby terminating units selection. The operation of the last.

.collntitlg relay closes a circuit to drive se quence. switch 500 into position It. The opening of the fundamental circuit deencrgizes relay 802. and a circuit; is established from battery. motor magnet. of sequence switch Stilt. sequence switch spring 816 top, hack contact and armature of relay 803 to ground. The sequence switclrleaves position ti and in the. positions between 6 audit, the usual testing! and ringing operations take place.

amL for the sake of -elearness. the sequence switch positions corresponding thereto 'are audihlv announcing: the number of the de' sired line. and automatic means for connet-ting su h announcing means to the telcphone oi such second operator;

2. telephone exchange system including telephone lines extending to an o 'a-ratoi"s position. trunk lines extending: from such operators position to a second operators position, int-ans under the. control of thefirst operator for connecting the calling line to one of such trunk lines. means for midi-- hly announcing the number of the'desired line means for automatically connecting such announcing means to such second operators telephone. in ans for automat icallydis connecting such announcing means, and means for manually discom'iecting such announcing means.

it A telephone exchange systen'i including telephone lines extendin; to an o eratoi"s position. trunl: lines extending from such operatofis position to a second opcrators position. means under the: control of the first ()Ptl'tll't)! for connecting'jhe allin; line to one of such trunk linesetineans for audihly annouucingthe numher oi the desired line. autonuitic means fo connecting"- such an- Mount-lug means to the telephone. of the second operator. and manual means under the r vggo .\s these operations are welt 'htmwlt. they Will not he further described control of. either operator for disconnecting such announcing means.

t. A telephone exchange system comprlsing means for connecting a calling line to \\hcthe|' the further extension of the cal is accomplished by another operator or byan "Eiutomatic selector switch.

.1. In a telephone exchange system, means for connecting calling to called lines includ-.-

inn a connecting circuit, an operatofis posi tion. an impulse sending device. and an audihle announcing device at. such position, an automatic switch also at such position, and means under the control of the operator for causing said automatic switch to associate either said impulse sending device or said audihle aiinouncing device with said circuit.

t'i. A telephone exchange system, an operators position. a connecting), circuit. at said operators position, trunk lines extending from said operators position to another op erato'r's positioiu other trunk linesextending from said first operators position terminab ing in automatic selector switches, a controlingequipment at said tiist operators position including an impulse sending device and an audihle announcing device. an automatic circuit changing switch associated with said controlling equipment means for driving,' said automatic circuit. changing switch through two complete cycles of movement. contacts operated hy said switch in the first c \'t'l( of movement for extracting said con-. Meeting circuit to a trunk linta contacts operated by said switch in its second cycle of movement for associating either said pulse sending device or said audihle announcin; device with said connecting circuit, and means under the control. of said tirst operator for determining the association with said connecting circuit of either of said devices to the exclusion of the other.

i'. A telephone exchange system comprise: inn means for connecting a calling line to :1 called line including a connecting circuit, a registering and controlling equipment, an impulse sending device and an audible announciug' device either of which may heatsociated with such connecting circuit and corn trolled h the set positions of the iegistfilS oi such taptipment. and means for determineontrolled by ing which of such devices is the extension such registers in controlling of a particular call.

H. A telephone exchange system includin; telephone linesextending to an 0 a tors position, a second operators position,

trunk lines extending between said 01mmi01s"p v .-;itiuns, means for (lSHUCiHi'iI'Jg said iines with said tlllllk'iillfifi, means for audibly amidn'lncing Una [llllllIHl' of :1 line, minus 5 under the cumin-0i of [he first OPGL'MLUI for detexn'iining H10 number zinnmnniml by said announcing nix-3mm, an upmxulmVs tclcphune set at Said second operators osition, and nut-(nimble means for assoclatlng sald annonnvnig means and Said operators tale-1,0

phone sob with one ofsaid trunk lines.

In witness whereof, I hereunto subscribe my munc this 15th day of June, A. l). 1916.

ALBEN E. LUNDELL. 

